/*
 * Copyright (c) 2011, Marc-Andre Ferland - madrang@gmail.com
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the The Warrent Team nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *     * This software is free for non-commercial use. You may not use this
 *       software, in whole or in part, in support of any commercial product
 *       without the express consent of the author.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE WARRENT TEAM BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
using System;
using System.Runtime.InteropServices;

namespace OsHelper.UsbNet.LibUsb.Descriptors
{
	public class EndpointDescriptor : UsbNet.Descriptors.EndpointDescriptor
	{
		public EndpointDescriptor (IntPtr MyHandle) : base(MyHandle, Marshal.SizeOf(typeof(EndpointInfo)))
		{
		}
		public EndpointDescriptor (SafeHandle MyHandle) : base(MyHandle, Marshal.SizeOf(typeof(EndpointInfo)))
		{
		}

		[StructLayout(LayoutKind.Sequential)]
		internal class EndpointInfo
		{
			public readonly byte Length;
			public readonly UsbNet.Descriptors.DescriptorType DescriptorType;
			public readonly byte EndpointAddress;
			public readonly UsbNet.Descriptors.EndpointAttributes Attributes;
			public readonly short MaxPacketSize;
			public readonly byte Interval;

			/// <summary>
			/// For audio devices only: the rate at which synchronization feedback is provided.
			/// </summary>
			public readonly byte Refresh;

			/// <summary>
			/// For audio devices only: the address of the synch endpoint.
			/// </summary>
			public readonly byte SynchAddress;

			/// <summary>
			/// Extra descriptors.
			/// If libusb encounters unknown endpoint descriptors,
			/// it will store them here, should you wish to parse them.
			/// </summary>
			public readonly IntPtr ExtraBytesHandle;

			/// <summary>
			/// Length of the extra descriptors, in bytes.
			/// </summary>
			public readonly int ExtraLength;
		}
		
		/// <summary>
		/// Extra descriptors.
		/// If libusb encounters unknown endpoint descriptors, it will store them here, should you wish to parse them.</summary>
		public override byte[] ExtraBytes {
			get {
				EndpointInfo Inf = (EndpointInfo)Marshal.PtrToStructure (this.DangerousGetHandle (), typeof(EndpointInfo));
				
				if (Inf.ExtraLength <= 0)
					return new byte[0];
				
				byte[] bytes = new byte[Inf.ExtraLength];
				Marshal.Copy (Inf.ExtraBytesHandle, bytes, 0, bytes.Length);
				return bytes;
			}
		}
	}
}
